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问题 选择题

飞机上升了-80米，实际上是（　　）

A．上升80米

B．下降-80米

C．先上升80米，再下降80米

D．下降80米

答案

负号表示与上升意义相反，即下降，则飞机上升了-80米，实际上是下降80米．

故选D．

单项选择题 共用题干题

A requirement is simply a statement of what the system must do or what characteristics it needs to have. Requirements written from the perspective of user and focus on user needs are called (1). Requirements written from the developer's perspective and describe how the system will be implemented are called (2). Requirements evolve from detailed statements of the business capabilities that a system should have to detailed statements of the technical way in wluch the capabilities will be implemented in the new system. Requirements can be either functional or nonfunctional in nature. For example, during the analysis phase of travel vehicles sales system, the system that must have the ability to search for available inventory is (3). The requirement that the system should be able to work on any Web browser belongs to (4). That customer personal information is protected in compliance with the Data Protection Act is a requirement of (5).

空白（4）处应选择（）

A.functional requirement

B.technical requirement

C.operational requirement

D.information requirement
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单项选择题

人体软组织中的声速大约是（）

A.1540m/s

B.350m/s

C.4500m/s

D.3000m/s

E.7000m/s
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